Image Compressor

No. Every step - decoding, resizing, compression and ZIP packaging - runs entirely inside your browser using WebAssembly codecs. Your images never leave your device and nothing is sent to a server, so it works offline and is safe for private or sensitive photos.

You can drop PNG, JPG, WebP, AVIF, GIF or BMP images. You can export to WebP, AVIF, MozJPEG (JPEG) or PNG (optimised with OxiPNG). WebP and AVIF usually give the smallest files at good quality; JPEG is the most universally supported; PNG stays lossless.

Instead of picking a quality level, you set a kB budget (for example "max 200 kB") and the tool automatically searches for the highest quality that still fits under that size, separately for each image. It only aims at the weight - it never judges whether the result looks good, so you stay in control by watching the before/after preview.

The tool encodes at the lowest sensible quality and then tells you the truth - for example "couldn't hit 50 kB - got 78 kB" - instead of pretending it succeeded or wrecking the image. It never downscales the resolution on its own; if you want a smaller file you can lower the resolution yourself with the resize option.

Yes. Drop multiple files, a whole folder, or a ZIP archive. Each image keeps its own settings - a new one inherits whatever you last used - so you tune the one you are previewing without touching the rest. To put the current settings on several images at once, select them and use "Apply current settings". Then download them individually or grab the whole batch as a single ZIP.

A converter changes the container format (PNG to JPG, HEIC to JPG) with a simple quality slider. This compressor fights for the smallest possible weight using the same WebAssembly codecs as Squoosh - MozJPEG, WebP, AVIF and OxiPNG - plus a before/after slider and target-size search. If you only need a different format, an image converter is the lighter tool.

JPEG has no alpha channel, so transparent areas have to be filled. When you export a transparent image to JPEG, the tool flattens it onto a background colour - white by default, but you can pick any colour with the "Background when flattened" swatch - and tells you it did so. To keep transparency instead, export to WebP, AVIF or PNG and leave "Preserve transparency" on.